import com.oracle.webservices.internal.api.databinding.DatabindingMode;

import java.util.HashMap;

/**
 * @Classname BinaryTree 二叉树：每个节点最多只能有两个子节点的形式称为二叉树；满二叉树：所有的叶子节点都在最后一层，层数为2^n-1
 * @Description TODO
 * @Date 2021/11/24 16:59
 * @Created K024851
 */
public class BinaryTreeDemo {

    public static void main(String[] args) {
        BinaryTree binaryTree =new BinaryTree();
        HeroNode root  = new HeroNode(1,"宋江");
        HeroNode node2 = new HeroNode(2,"吴用");
        HeroNode node3 = new HeroNode(3,"卢俊义");
        HeroNode node4 = new HeroNode(4,"林冲");
        HeroNode node5 = new HeroNode(5,"关胜");
        //创建二叉树
        root.setLeft(node2);
        root.setRight(node3);
        node3.setLeft(node4);
        node3.setRight(node5);
        binaryTree.setRoot(root);
        //测试：
        System.out.println("前序");
        binaryTree.preOrder();

        System.out.println("中序");
        binaryTree.infixOrder();
        System.out.println("后序");
        binaryTree.postOrder();

        //查找
        System.out.println("");

        //删除：
        binaryTree.preOrder();
        binaryTree.delNode(5);
        binaryTree.preOrder();
    }
}

//定义二叉树
class BinaryTree {
    private HeroNode root;
    public void setRoot(HeroNode root){
        this.root = root;
    }
    //前序遍历
    public void preOrder(){
        if (this.root !=null){
            this.root.preOrder();
        }else {
            System.out.println("二叉树为空，无法遍历");
        }
    }
    //中序遍历
    public void infixOrder(){
        if (this.root !=null){
            this.root.infixOrder();
        }else {
            System.out.println("二叉树为空，无法遍历");
        }
    }
    //后续遍历
    public void postOrder(){
        if (this.root !=null){
            this.root.postOrder();
        }else {
            System.out.println("二叉树为空，无法遍历");
        }
    }
    //--------------------------------- 序号查找
    public HeroNode preOrderSearch(int no){
        if (root!=null){
            return root.preOrderSearch(no);
        }else {
            return null;
        }
    }
    public HeroNode infixOrderSearch(int no){
        if (root !=null){
            return  root.infixOrderSearch(no);
        }else {
            return null;
        }
    }
    public HeroNode postOrderSearch(int no){
        if (root !=null){
            return postOrderSearch(no);
        }else {
            return null;
        }
    }

    //删除节点：
    public void delNode(int no){
        if (root !=null){
            if (root.getNo() ==no){
                root =null;
            }else {
                root.delNode(no);
            }
        }else {
            System.out.println("空树，不能删除---");
        }
    }
}

//定义节点
class HeroNode {
    private int no;
    private String name;
    private HeroNode left;
    private HeroNode right;

    public HeroNode(int no, String name) {
        this.no = no;
        this.name = name;
    }

    public int getNo() {
        return no;
    }

    public void setNo(int no) {
        this.no = no;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public HeroNode getLeft() {
        return left;
    }

    public void setLeft(HeroNode left) {
        this.left = left;
    }

    public HeroNode getRight() {
        return right;
    }

    public void setRight(HeroNode right) {
        this.right = right;
    }

    @Override
    public String toString() {
        return "HeroNode{" + "no=" + no + ", name='" + name + '\'' + '}';
    }

    //前序遍历
    public void preOrder() {
        System.out.println(this);//先输出父节点

        if (this.left != null) {
            this.left.preOrder();
        }
        if (this.right != null) {
            this.right.preOrder();
        }
    }

    //中序遍历
    public void infixOrder() {

        if (this.left != null) {
            this.left.infixOrder();
        }
        System.out.println(this);
        if (this.right != null) {
            this.right.infixOrder();
        }
    }

    //后序遍历
    public void postOrder() {
        if (this.left != null) {
            this.left.postOrder();
        }
        if (this.right != null) {
            this.right.postOrder();
        }
        System.out.println(this);
    }

//---------------------遍历查找
    public HeroNode preOrderSearch(int no){
        System.out.println("进入前序遍历");
        //1、判断当前节点
        if (this.no == no){
            return this;
        }
        HeroNode resNode = null;
        //2、左递归查询
        if (this.left !=null){
            resNode = this.left.preOrderSearch(no);
        }
        if (resNode != null){
            return resNode;
        }
        if (this.right !=null){
            resNode = this.right.preOrderSearch(no);
        }

        return resNode;
    }
    //中序
    public HeroNode infixOrderSearch(int no){
        HeroNode resNode = null;
        if (this.left !=null){
            resNode = this.left.infixOrderSearch(no);
        }
        if (resNode != null){
            return  resNode;
        }
        if (this.no ==no){
            return this;
        }
        if (this.right !=null){
            resNode =this.right.infixOrderSearch(no);
        }
        return resNode;
    }
    //后续
    public HeroNode postOrderSearch(int no){
        HeroNode resNode =null;
        if (this.left !=null){
            resNode = this.left.postOrderSearch(no);
        }
        if (resNode != null){
            return  resNode;
        }
        if (this.right !=null){
            resNode = this.right.postOrderSearch(no);
        }
        if (resNode !=null){
            return resNode;
        }
        if (this.no ==no){
            return this;
        }
        return  resNode;
    }
//--------------------删除 叶子节点：删除节点  非叶子节点：删除子树
    public void delNode(int no){
        //当前节点的左子节点不为空，并且左子节点为要删除的节点
        if (this.left !=null && this.left.no ==no){
            this.left = null;
            return;
        }
        //当前节点的右子节点不为空，且右子节点为要删除的节点
        if (this.right!=null && this.right.no ==no){
            this.right =null;
            return;
        }
        //不是前两者，左遍历找到符合上两者的
        if (this.left !=null){
            this.left.delNode(no);
        }
        //不是前三者。又遍历
        if (this.right !=null){
            this.right.delNode(no);
        }
    }
}